In the browser interface, it's possible to set the avatar of a channel to a custom image, and these appear in the browser chat client instead of the big letter. But they don't appear in the mobile client.
1.In the Browser version, set a custom avatar image on any channel
The channel with the custom avatar has that avatar displayed.
Like it does in the browser:

The channel with the custom avatar has a letter as an avatar.

Hi @robertfromont I'm already working on this feature, soon we'll see custom avatars on the channels in the mobile app. take a look here #2454 :)
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Hi @robertfromont I'm already working on this feature, soon we'll see custom avatars on the channels in the mobile app. take a look here #2454 :)